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سؤال 198

How close to the upper edge of a band’s phone segment should your displayed carrier frequency be when using 3 kHz wide USB?

  1. At least 3 kHz above the edge of the band
  2. At least 3 kHz below the edge of the bandپاسخ درست
  3. At least 1 kHz above the edge of the segment
  4. At least 1 kHz below the edge of the segment

توضیح

With USB the occupied spectrum lies entirely above the displayed carrier frequency, so a 3 kHz wide signal needs its displayed frequency at least 3 kHz below the upper edge to stay inside. Placing that margin above the edge points it in the wrong direction and would put the whole emission outside the segment.

ادامهٔ این آزمون

شروع تمرین
سؤال 198: How close to the upper edge of a band’s phone segment… · FCC General Class (Element 3) · Questena